docs: def separated(self):
          """
          Create a separate Label-List for every distinct label-value.
  
          Returns:
              dict: A dictionary with distinct label-values as keys.
                    Every value is a LabelList containing only labels with the same value.
  
          Example:
              >>> ll = LabelList(idx='some', labels=[
              >>>     Label('a', start=0, end=4),
              >>>     Label('b', start=3.95, end=6.0),
              >>>     Label('a', start=7.0, end=10.2),
              >>>     Label('b', start=10.3, end=14.0)
              >>> ])
              >>> s = ll.separate()
              >>> s['a'].labels
              [Label('a', start=0, end=4), Label('a', start=7.0, end=10.2)]
              >>> s['b'].labels
              [Label('b', start=3.95, end=6.0), Label('b', start=10.3, end=14.0)]
          """
          separated_lls = collections.defaultdict(LabelList)
  
          for label in self.labels:
              separated_lls[label.value].add(label)
  
          for ll in separated_lls.values():
              ll.idx = self.idx
  
          return separated_lls